Question

1. Thu gọn biểu thức

a) (x-3) ² + 3x (x-5)

b) (3x+2) ² - (x+3) (x-3)

2. Tìm x biết a) (x+4) ² - (x+2) (x-2)=5

b) (3x-1) ² _ (2x-3) (4x+1)= 5+x ²

Answer 1

1. Thu gọn biểu thức - Hoc24 làm rồi mà bạn?

Answer 2

1.

a) \(=x^2-6x+9+3x^2-15x=4x^2-21x+9\)

b) \(=9x^2+12x+4-x^2+9=8x^2+12x+13\)

2.

a) \(\Leftrightarrow x^2+8x+16-x^2+4-5=0\\ \Leftrightarrow8x=-15\\ \Leftrightarrow x=-\dfrac{15}{8}\)

b) \(\Leftrightarrow9x^2-6x+1-8x^2+12x-2x+3-5-x^2=0\\ \Leftrightarrow4x=1\\ \Leftrightarrow x=\dfrac{1}{4}\)

Answer 3

1,a,=x2−6x+8+3x2−15x=4x2−21x+8b,=9x2+12x+4−x2+9=8x2+12x+132,a,⇔x2+8x+16−x2+4=5⇔8x=−15⇔x=−158b,⇔9x2−6x+1−8x2−2x+12x+3−x2=5⇔4x=1⇔x=14